Rotating tendon anchor

ABSTRACT

A tendon anchor is used for attaching a tendon to a bone without sutures within a cylindrical bore drilled into the bone. The tendon anchor is adapted for insertion into the bore of a bone and has a generally elongated rectangular shape with opposite ends thereon. The tendon anchor has a transverse hole therein adapted to receive a central portion of the tendon and when the tendon anchor (with a tendon threaded into the hole therein) is inserted in the bore in the bone longitudinally, exerting force upon the ends of the tendon causes the tendon anchor to rotate to a partially transverse position within the bore thus forcing opposite end portions of the anchor into engagement with the cylindrical bore in the bone thereby securing the tendon in the bone.

The present application is a continuation of U.S. Patent Application ofRobert S. Supinski for “Tendon Anchors”, U.S. Ser. No. 09/668,993, filedSep. 25, 2000 now U.S. Pat. No. 6,579,295.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to tendon anchors. More specifically, itrelates to tendon anchors utilized to attach tendons to one or morebones without sutures and through a single bore drilled into the bone.

2. Description of the Prior Art

The need to effectively and efficiently attach a tendon to a bone isabsolutely critical in a number of orthopedic surgical procedures. Themost common current practice is to utilize a device called a sutureanchor to attach a suture to the bone and thereafter tie the tendon tothe suture thereby making the attachment of the tendon to the bone.Examples of this practice are set forth in U.S. Pat. Nos. 5,961,538;5,944,724; 5,906,624; and 5,904,704. While such techniques arereasonably effective, the use of suture anchors is overly time consumingand creates unnecessary risks of failure. For example, the suture maybecome detached from the anchor or the tendon and the process ofsuturing the tendon to the anchor may actually weaken the strength ofthe tendon itself or cause it to tear. It is believed that a bettertechnique would involve a direct attachment of the tendon itself to atendon anchor which is secured within the bone.

One known process which is believed to be a step in the right directionis disclosed in a publication entitled “Bone Mulch Screw/WasherLocDevice For the New Millennium” published by Arthrotek, a Biomet Company.The publication is undated but is believed to have been published inearly 2000 and not earlier than the later part of 1999. This publicationdiscloses an ACL reconstruction technique in which a tendon isultimately attached directly to the bone by means of tendon anchors.While sutures are not utilized to attach the tendon to the bone, theprocess still requires the use of a suture (pp. 9-10) attached to oneend of the tendon to pull the tendon over a transverse cross beam of thefemoral anchor. Such a process is overly complex and unnecessarily timeconsuming.

Further, the Arthotek device itself is overly complex and utilizes atleast one tendon anchor which requires drilling two separate bores intothe femur, one longitudinally through which the tendon is threaded andone transversely to provide a cross beam over which the tendon is passed(see FIG. 25 of publication). Drilling an extra bore into the bone takesmore time, requires precision to make certain that the two bore holesintersect, causes increased trauma to the patient and can weaken theoverall structure of the bone. Thus, while this technique provides animprovement over prior art devices which require suturing a tendon to asuture anchor (sometimes called bone anchor), there remains a need for asimple, easy to install tendon anchor which does not require sutures atall during the installation procedure and which only require thedrilling of a single bore into the bone.

IN THE SUMMARY OF THE INVENTION

The present invention meets this need by providing a number ofdifferently designed tendon anchors which each include a channel toreceive and hold a tendon which is inserted into a single bore in thebone with the anchor. Thus, no sutures are required and only a singlebore hole is needed.

In its simplest form, the present invention provides a tendon anchor forattaching a tendon to at least one bone without sutures within a boredrilled into said at least one bone comprising a first tendon, anchoradapted for insertion into said bore of a first bone, said first tendonanchor having a channel provided therein for receiving and holding acentral portion of a tendon during insertion and when in final positionin the bore of said first bone with opposite ends of the tendonextending out of the singular bore; and a first securing meansassociated with said first tendon anchor for moving at least a part ofthe first tendon anchor radially outward to securely engage the firsttendon anchor and the central portion of the tendon to the first bone byurging at least a part of the first tendon anchor against a cylindricalwall portion of said bore in said first bone.

Preferably, said first tendon anchor is generally cylindrical in shapewith a cylindrical outer wall and has a crescent shaped recess therein,said recess extending longitudinally along a cylindrical wall portionthereof from one end portion of the first tendon anchor to a location atleast two-thirds of the distance toward an opposite end portion thereof.

Preferably, said first securing means is a first tapered screw adaptedto be received between a cylindrical wall of the bore in said first boneand said threaded recess, whereby tightening said first screw causes oneside of the first screw to embed itself into a cylindrical wall of thebore and an opposite side of the first screw urges a portion of thefirst tendon anchor opposite said crescent shaped recess and the entiretendon anchor radially outward against an opposite cylindrical wall ofthe bore.

In a presently preferred embodiment of the invention, said cylindricallyouter wall portion of said first anchor means is provided with outwardprojections thereon to aid in engaging said outer wall portion of thefirst tendon anchor to the cylindrical wall of the bore.

Preferably, said cylindrically shaped first tendon anchor has atransverse hole therein which forms said channel, said transverse holeextending from opposite cylindrical walls and positioned transversely tothe crescent shaped recess and wherein said tendon is threaded throughsaid transverse hole whereby a central portion thereof is positionedwithin said transverse hole.

In many cases, the invention will utilize two tendon anchors. In suchcases, a second tendon anchor is provided which is adapted for insertioninto a bore drilled into a second bone; and a second securing meansassociated with said second tendon anchor for moving at least a part ofthe second tendon anchor radially outward to securely engage the secondtendon anchor and the end portions of the tendon to the second bone byurging at least a part of the second tendon anchor against a cylindricalwall portion of said bore in said second bone.

Preferably, said second tendon anchor is also generally cylindrical inshape with a cylindrical outer wall and has a crescent shaped recesstherein, said recess extending longitudinally along and entirecylindrical wall portion thereof from one end portion of the secondtendon anchor to an opposite end portion thereof.

Preferably, said second securing means is a second tapered screw adaptedto be received between a cylindrical wall of the bore in said secondbone and said threaded recess, whereby tightening said second screwcauses one side of the second screw to embed itself into a cylindricalwall of the bore in the second bone and an opposite side of the secondscrew urges a portion of the second tendon anchor opposite said crescentshaped recess and the entire second tendon anchor radially outwardagainst an opposite cylindrical wall of the bore in said second bone.

In the preferred embodiment, said cylindrically outer wall portion ofsaid second anchor means is provided with outward projections thereon toaid in engaging said outer wall portion of the second tendon anchor tothe cylindrical wall of the bore of the second bone.

Preferably, said cylindrically shaped second tendon anchor has notchestherein to receive the opposite ends of said tendon and said ends ofsaid tendon are compressed and held in place between the cylindricalwall of the bore of the second bone and said cylindrical outer wall ofthe second tendon anchor.

In an alternative embodiment of the invention, said first tendon anchorhas a generally elongated rectangular shape with opposite ends thereofhaving engaging portions thereon adapted to engage into the cylindricalwall of the bore in the first bone, said first tendon anchor having asecuring means in the form of a transverse hole therein adapted toreceive a central portion of said tendon, said hole also constitutingsaid channel, said hole being closer to one end of the first tendon thanthe other anchor and closer to one side of the tendon anchor than theother, whereby said first tendon anchor with a tendon threaded into saidhole therein is inserted into the bore in the first bone longitudinallyand upon exerting force upon the ends of the tendon, said first tendonanchor rotates to a partially transverse position within the bore thusforcing said engaging portions into the cylindrical bore in the firstbone thereby securing the tendon in said first bone.

In yet another embodiment of the invention, said first tendon anchor isformed of a first elongated member and a second elongated member, saidfirst and second members each having an engaging portion on at least oneend thereof adapted to engage into the cylindrical wall of the bore inthe first bone, said first and second members having a channel providedin one end thereof for receiving and holding a central portion of atendon during insertion and when in final position in the bore in saidfirst bone, said first and second elongated members engaging one anotherat a location intermediate the end portions thereof and adapted to moverelative to one another in a scissor like fashion whereby said membersare inserted into the bore of the first bone in a substantially closedscissor position with the central portion of the tendon engaged and heldin the channel of each member and whereby exerting force upon the endsof the tendon causes the members to move to an open scissor positionforcing the engaging portion of each member into the cylindrical bore inthe first bone thereby securing the tendon in said first bone.

In this embodiment, exerting greater force on the tendon ends causessaid engaging portion to embed more deeply into the cylindrical bore inthe first bone thereby more securely holding the tendon in said firstbone.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a human knee having a single bore holedrilled therein.

FIG. 2 is a perspective view of a solid inserter rod adapted forinsertion into said single bore hole.

FIG. 3 is a perspective view of a hollow guide tube adapted to be tappedinto the bones guided by said solid inserter rod.

FIG. 4 is a perspective view of the presently preferred first tendonanchor with the securing means in the form of a threaded screw attachedand also showing a screw driver and the tendon.

FIG. 5 is a front plan view of the presently preferred first tendonanchor of the present invention.

FIG. 6 is a side plan view of the presently preferred first tendonanchor of the present invention.

FIG. 7 is a top plan view of the presently preferred first tendon anchorof the present invention.

FIG. 8 is a side plan view of the presently preferred first securingmeans of the present invention.

FIG. 9 is a perspective view of the presently preferred second tendonanchor with the second securing means in the form of a threaded screwattached in a second bone and also showing the ends of a tendon.

FIG. 10 is a perspective view of the presently preferred second tendonanchor.

FIG. 11 is a front plan view of the presently preferred second tendonanchor.

FIG. 12 is a rear plan view of the presently preferred second tendonanchor.

FIG. 13 is a perspective view of a first tendon anchor havingprojections on an outer surface thereof in the form of teeth andthreads.

FIG. 14 is a perspective view of a second tendon anchor havingprojections on an outer surface thereof in the form of teeth andthreads.

FIG. 15 is a front plan view of one member of an alternative embodimentof a first tendon anchor which comprises two identical members.

FIG. 16 is a rear plan view of one member of an alternative embodimentof a first tendon anchor which comprises two identical members.

FIG. 17 is a perspective view of one member of an alternative embodimentof a first tendon anchor which comprises two identical members.

FIG. 18 is a perspective view of one member of an alternative embodimentof a first tendon anchor which comprises two identical members from adifferent perspective.

FIG. 19 is a side elevational view showing both members of analternative first tendon anchor which comprises two identical members ina closed scissor position.

FIG. 20 is a perspective view showing both members of an alternativefirst tendon anchor which comprises two identical members in an openscissor position.

FIG. 21 is a side elevational view showing yet another alternativeembodiment of a first tendon anchor which shows the anchor in a verticalinsertion position.

FIG. 22 is a side elevational view showing of yet another alternativeembodiment of a first tendon anchor which shows the anchor in atransverse engaging position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the figures, the presently preferred embodiments of thepresent invention will be described in connection with an ACLreconstruction. While this detailed description relates to theattachment of a tendon between a femur and a tibia bone located withinthe knee of a patient, it is to be understood that the invention is notlimited thereto. A similar tendon anchor could be utilized to secure atendon to any bone within the human body.

Referring to FIG. 1, a human knee 10 is shown. A femur bone 20, a tibiabone 30 and a fibia bone 31 are shown. A singular bore hole 40 a, 40 bis drilled into the knee beginning at point 41 in the tibia and endingat point 42 in the femur. Thus, a singular drilling action is utilizedto drill through both the tibia and the femur.

Once the tibial tunnel 40 b and femoral tunnel 40 a are created bytechniques which are well known in the field, end 52 of a solid inserterrod 50 (FIG. 2) is tapped into the tibial tunnel 40 b and femoral tunnel40 a. The inserter rod 50 includes a removable head 54 which is screwedinto the inserter at location 56. It will be obvious that by merelytwisting end 54 relative to rod 50, end 54 may be removed from the rod50. Once the solid inserter rod is tapped completely into the tibialtunnel 40 b and femoral tunnel 40 a, the inserter rod end 54 is removedand a hollow guide tube 60 (FIG. 3) beginning with end 62 thereof istapped over the rod 50 into position within the tibial tunnel 40 b andfemoral tunnel 40 a. The hollow guide tube is tapped at end 64 thuscausing the projections 62 to embed themselves into the bone at end 42of the femoral tunnel 40 a. Once the hollow guide tube is inserted, thescrew end 54 is screwed into the solid rod 50 and solid rod 50 isremoved from the tibial tunnel 40 b and femoral tunnel 40 a.

Once the hollow guide tube is properly inserted, the assembly shown inFIG. 4 is inserted within the interior 66 (FIG. 3) of the hollow guidetube 60. This assembly includes a first tendon anchor 80 (which is shownin FIGS. 4 through 7) and a securing means 100 in the form of a threadedscrew (which is shown in FIGS. 4 and 8) as well as a tendon 5 which hasa central portion 6 and end portions 7 and 8. A long handled screwdriver101 is shown inserted into the first securing means 100. It is notedthat the tendon 5 is threaded through a hole 86 provided in the firsttendon anchor. The tendon is threaded through hole 86 prior to insertionin the guide tube.

As can be seen in FIGS. 4 through 7, the first tendon anchor has acrescent shaped recess 82 provided therein which has external threads 84which are adapted to mesh with threads 104 of screw 100. It is notedthat the crescent shaped recess does not extend the whole length of theanchor means but that a small guide pin hole 88 does extend completelythrough the first tendon anchor 80. The guide pin hole 88 is positionedto receive a guide pin 110 which is attached to the entry end of screw100. The opposite end 102 of screw 100 is provided with receiving meansto receive the end of a screw driver 101.

Once the assembly of FIG. 4 is inserted within the guide tube 60 to theend 42 of the femoral tunnel 40 a, the guide tube 50 is withdrawn andthe screw 100 is tightened. Because screw 100 is tapered as best shownin FIG. 8, this causes the outer surface 81 of the first tendon anchorto be pushed radially outward into the femoral tunnel engaging itagainst the femoral tunnel. Likewise, one side 106 of the screw member100 will engage itself in an opposite side of the femoral tunnel 40 a.Once fully tightened, screw driver 101 is removed from the tibial tunnel40 b and femoral tunnel 40 a thereby leaving tendon ends 7 and 8extending out of the opening 41 of the tibial tunnel 40 b.

Referring to FIGS. 9 through 12, a second tendon anchor is shown anddescribed. This tendon anchor is similar in principle to the firsttendon anchor but differs slightly in structure. As shown in FIG. 9, thesecond tendon anchor 180 is shown as positioned within end 41 of thetibial tunnel 40 b. Ends 7 and 8 of the tendon extend out of the tibialtunnel and are secured against the wall of the tibial tunnel by outsidesurface 181 of the second tendon anchor 180. As shown in FIGS. 9, 10 and11, a crescent shaped recess 182 is provided in the second tendon anchorwhich extends the full length of the tendon anchor. As with the firsttendon anchor, second tendon anchor 184 has threads 184 provided in therecess 182 which are adapted to mesh with threads 204 of screw 200(which constitutes the second securing means). Screw 200 is adapted forinsertion by means of a screw driver which enters the recess at 202. Asbest shown in FIGS. 10, 11 and 12, the second tendon anchor 180 istapered with insertion end 186 being smaller in diameter than outer end187. It is also noted that notches 189 are provided in the outer end 187for securely holding the ends 7 and 8 of tendon 5 in a desired position.The ends 7 and 8 of tendon 5 may then be trimmed once the screw 200 isfully engaged. As with the first tendon anchor, tightening the screw 200forces outer surface 181 radially outward into the end 41 of the tibialtunnel 40 b.

FIGS. 13 and 14 are provided to show that it is preferable to providesome type of projections on the outer surface 81′ and 181′ of the firsttendon anchor 80′ and the second tendon anchor 180′. These projectionsmay take the form of teeth 81′ and 183′ or in the form of threads orridges as shown at 85′ and 185′. It will be obvious to the reader thatthese projections 81′, 85′, 183′ and 185′ are designed to engage intothe bone of the femoral tunnel 40 a and tibial tunnel 40 b.

FIGS. 15 through 19 show an alternative embodiment of a first tendonanchor according to the present invention. In this embodiment, as bestshown in FIG. 19, two identical members 400 and 400′ are provided. Thedetails of the members 400 and 400′ are identical and thus only one ofsuch members will be described in detail. Essentially, the members 400and 400′ act like a pair of scissors and are adaptable for rotationbetween a closed scissor position and an open scissor position bydownward force on ends 7 and 8 of the tendon 5. Pulling downward on ends7 and 8 causes the central portion 6 of tendon 5 to exert force on themembers 400 and 400′ thus opening the members causing engaging means 405and 405′ to engage within the femoral tunnel 40 a.

Referring to FIGS. 15 through 18, the details of the member 400 (and400′) will be described. Essentially, member 400 is in the form of acylindrical body which has been cut longitudinally in half. FIG. 15shows a front view of member 400 which is essentially flat. Member 400includes a main body portion 401 into which a notch 410 is provided.This notch is to allow for the mating of an identical member 401′ and toallow a scissor action to occur. Also provided on the flat surface asshown in FIG. 15 is a channel 402 which is adapted to initially receiveand hold the central portion 6 of a tendon 5 during insertion. It isnoted that the channel 402 includes a ramp like surface 403 whichfacilitates opening of the members upon the downward force of thecentral portion 6 of a tendon.

FIG. 16 shows the rear of the member 400 with similar parts shown. Aninclined surface 412 is provided which essentially allows the members toopen more widely. Engaging teeth 405 are provided at end 404 of themember.

FIG. 19 shows the members 400 and 400′ in a closed scissor position withthe tendon 5 being held within the channels 402 and 402′. The assemblyas shown in FIG. 19 is inserted within the hollow guide tube 60 and ispushed by a push member 500 into the femoral tunnel to end 42 thereof.The hollow guide tube member 60 is then withdrawn. Upon a pulling actionof ends 7 and 8 which extend outside of the end 41 of the tibial tunnel40 b, causes the members 400 and 400′ to rotate to an open scissorposition as shown in FIG. 20. This causes the engaging teeth 405 and405′ to engage within the cylindrical wall of the femoral tunnel 40 asecuring the anchor firmly in the desired position. It is noted becauseof the mechanics involved that the greater the tension on ends 7 and 8,the greater the outward force of ends 404 and 404′ thus providinggreater resistance and a stronger resistance to pull out of the anchor.

It will be obvious to the reader that the process of simply insertingthe assembly into a hollow guide tube 60 as shown in FIG. 19, removingthe tube and simply pulling on the ends 7 and 8 to engage the anchor isa far faster and far simpler device than has been heretofore proposed.

FIGS. 21 and 22 show yet another embodiment of a first tendon anchor300. The tendon anchor 300 is generally rectangular in shape and hasengaging teeth portions provided at the corners 322 thereon. An opening310 is provided through the first tendon anchor member 300 at a locationin the top right quadrant as shown in FIG. 21. The opening 310 is in theform of a hole which is located closer to one end (a hole end) than toan opposite end and is located closer to one side (a hole side) than toan opposite side. By having the opening 310 above the center of therectangular member and off the longitudinal axis thereof, the locationof the hole facilitates a rotation of the member within the femoraltunnel 40 a. The device is positioned longitudinally for insertion asshown in FIG. 21 and may be pushed into position in much the same manneras the device described with respect to FIG. 19. Once in position,merely pulling the ends 7 and 8 of the tendon 5 downwardly causes thefirst anchor member 300 to rotate from a longitudinal position to atransverse position with corner teeth 322 and 332 engaging thecylindrical wall of the femoral tunnel 40 a. While the particularoperation of this tendon anchor is superficially similar to a deviceshown in FIG. 10 of U.S. Pat. No. 5,961,538, it is noted that thisdevice clearly does not anticipate nor teach the provision of a channelfor adapting to receive a tendon. Rather, that device relies upon theprior art method of using sutures to sew the tendon in place.

To briefly review the operation of all of the tendon anchor devicesdescribed herein, the process simply involves the drilling of a tunnel(in the example shown into the tibia and fibia of the knee), passing asolid rod into the tunnel thus created, impacting the hollow guide tubeover the solid rod and removing the solid rod, inserting theanchor/screw driver through the tibial tunnel into the femoral tunnel,removing the outer sheath, and either tightening the securing means orsimply pulling the ends of the tendon to engage the securing means.Finally, a second tendon anchor means in the form of a tibial plug isprovided and screwed into the tibial tunnel.

It is noted that the tendon anchors described herein may be made fromany suitable bio-compatible metal, absorbable materials or frombone/allograft.

It is anticipated that the present invention can be utilized with anyform of tendon be the same harvested from the hamstring or be itartificial.

While I have shown and described the presently preferred embodiment ofmy invention, the invention is not limited thereto and may be otherwisevariously practiced within the scope of the following claims:

1. A tendon anchor for attaching a tendon to at least one bone withoutsutures within a cylindrical bore drilled into said at least one bonecomprising a tendon anchor adapted for insertion into said bore of abone, said tendon anchor having a generally elongated rectangular shapewith opposite ends thereon, each of said opposite ends of said tendonanchor having an engaging portion thereon adapted to engage acylindrical wall of the bore in the bone, said tendon anchor having atransverse hole therein, said transverse hole located closer to a holeend of said tendon anchor than to an opposite end thereof and said holelocated closer to a hole side of the tendon anchor than to an oppositeside thereof, through which transverse hole a central portion of saidtendon is received whereby when said tendon anchor with a tendonthreaded into said hole therein is inserted in the bore in the bonelongitudinally, exerting force upon the ends of the tendon solely causessaid hole end of said tendon anchor to rotate toward said hole side to apartially transverse position within the bore thus forcing said oppositeend portions into engagement with the cylindrical bore in the bonethereby securing the tendon in said bone.
 2. A tendon anchor accordingto claim 1 wherein said engaging portion further comprises a recessedportion in a middle portion of each said end and a pair of triangularextensions along each side of each said end.